A common step in the fabrication of garments and other related products is the sewing of a binding or facing to a fabric. A binding may thus be sewn to the edge of a tablecloth or bedspread, the hem of a dress or an apron. In its most traditional form, binding or other related operations are performed by a sewing machine operator who feeds the edge of the textile material and a strip of material into the machine simultaneously while forming the strip in such a manner that it is sewn to the textile with the desired configuration.
Naturally, performance of this operation demands the services of a highly skilled sewing machine operator. In an attempt to provide an alternative, a number of attachments have been designed for automatically feeding a strip or ribbon into a sewing machne in such a manner that the strip is properly sewn to the base fabric. Such devices may be employed for a wide variety of purposes including a number of binding, folding and facing applications. One such device is disclosed in my U.S. Pat. No. 3,495,559. Generally, these devices have a number of guide surfaces which form the strip as it is drawn through the attachment. The strip is formed by the surfaces of the attachment which bear against and deflect it into the desired configuration for sewing.
Naturally, when the strip bears against the guide surfaces as it is drawn through the attachment, it experiences a certain amount of friction and is put under tension. Because many fabric strips tend to stretch under tension, the friction in the attachment causes them to be sewn to the fabric in a stretched condition. At the same time, the fabric is fed into the sewing machine in an unstretched condition. Thus, when the fabric with the fabric strip sewn to it leaves the machine, the binder tends to relax, thus puckering the base fabric.
In the past, the only answer to this problem was to use a strip which did not experience any significant stretching when fed through a binder or other attachment. This result could be achieved by using either a strip with a small coefficient of friction or one which is substantially inelastic. Naturally, the problems with regard to the puckering of a fabric are experienced in operations other than binding, including facing. The present invention allows such operations to be performed without puckering the fabric.